1. Field of the Invention
The invention relates to pallet jacks. More particularly, the invention relates to a system and method for operating and transporting a pallet jack loaded with packaged goods, wherein the packaged goods comprise consumer goods and/or raw materials for manufacturing, and wherein the pallet jack can be transported from a lower non-smooth surface to an upper surface.
2. Background Art
Manually operated pallet jacks are mechanical devices used primarily for interior applications in such locations as warehouses and some larger consumer stores. The term “manually” refers to the means for moving and operating the pallets jacks: typically, they use hydraulic, pneumatic or electric lifting mechanisms that an operator enables to lift goods. Pallet jacks typically have two or more tines or forks, that are placed under a pallet, upon which is stored the goods to be moved. In the U.S., loaded pallets are typically about 4 feet long by 4 feet wide, and can be between a couple of inches to as much as 8-10 feet in height. The major considerations in the maximum height are the weight to be lifted and the center of gravity.
Other types of pallet jacks include those that are completely or semi-automated. These pallet jacks can include an internal combustion engine or motor, or an electric or propane operated motor that drives the pallet jack according to mechanical inputs received from the operator. Some of these pallet jacks can place goods on pallet several stories in height (20′-40′).
As briefly discussed above, pallet jacks are usually operated in the interior of buildings, on substantially smooth, pre-stressed concrete floors. These floors are extremely smooth and extremely strong. Pallet jacks are generally designed to operate in such an interior environment, and usually have two small wheels located in the rear portion of the pallet jack, directly under the lifting mechanism. The tines, or forks, are located outwardly from the centrally located rear wheels (see FIG. 1 as an example of prior art pallet jack), and the lifting mechanism is located directly over the centrally located rear wheels. Such known pallet jacks are generally useful for lifting heavily loaded pallets, wherein the pallets have a length (measured in the same direction as the tines extend from the pallet jack) to width ratio of about 1.0 and less. That is, the prior art pallet jacks generally are used to lift pallets in which the width is usually the same or greater than the length. That is the most stable lifting configuration for these prior art pallet jacks.
As can be seen in the typical prior art pallet jack, the front and centrally located rear wheels are designed to be used on the substantially smooth surfaces inside warehouses on the pre-stressed concrete floors. Using these types of pallet jacks outside, on the rough terrain of a gravel parking lot would be ineffective at best, and possibly dangerous because of their instability in that type of environment. Furthermore, if the dimensions of the pallet the pallet jack were carrying was such that its width exceeds the width of the tines, and the pallet's length was longer than that of the tines, then again the pallet jack could be dangerous to operate. Further still, using the prior art jack as shown in FIG. 1 inside a retail environment, such as a convenience store, could scuff the polished floors because of the type of wheels that are typically used.
FIG. 2 illustrates a second type of device for carrying goods inside a retail environment. As can be seen, however, these types of devices lack any type of lifting mechanism, the rear wheels that pivot are too small for rough terrain (such as gravel parking lots) and the amount of goods they can lift are limited by structural limitations of the device. Furthermore, to use such a device shown in FIG. 2, a user will have to load each item and then unload each item. This type of repetitious activity can lead to repetitive motion injuries, accidents and thus increases costs for the manufacturer/distributor of the goods/products delivered by the device.
Thus, a need exists for a pallet jack that can operate on both non-smooth exterior and smooth interior surfaces with substantial ease, and that can also carry a significant amount of goods using differently shaped pallets, wherein the length to width ratios are about 2:1, 3:1 or even more.